This week, three months after news broke that four teens were accused of sexually assaulting a younger classmate in a Walker Middle School locker room, another troubling revelation made headlines. Nine students described as witnesses in the case had failed to report anything they saw until authorities questioned them.

By then, the 13-year-old victim said he had been attacked as many as a dozen times by fellow members of the flag football team. School officials acknowledged Friday no adults were present when the alleged attacks occurred.

How could this happen?

The explanation lies somewhere in the tricky power hierarchy of a middle school locker room, the social phenomenon of a group watching someone in distress and the devastating effects bullying can have on both the target and those who watch it unfold.

Roland Sweeting's son told sheriff's detectives he saw two teammates hold the victim down as a third teen used a hockey stick to poke him on one occasion. He couldn't see exactly where the victim was poked but said the boy was laughing after he fought to get away.

"He thought it was a practical joke," Sweeting said of his son. "He thought they carried it too far. At that age, you're too young to really understand."

The sheer number of witnesses and occurrences in the case confounded school administrators and board members.

"I'm very surprised that this was taking place and nothing was said," School Board member Jack Lamb said. "It's kind of amazing."

Fellow board member Jennifer Faliero was similarly perplexed.

"If they watched someone be violated, whoever saw it, it makes you at least say, 'Gosh, Mom, someone had a hockey stick … ,' " she said. "Or maybe it was so disturbing that they didn't want to think that was happening."

The witness accounts don't tell a cohesive story.

In court records, some reported hearing only an argument between one of the attackers and the victim, while others recalled seeing the victim's shorts down and a hockey stick and broom handle being used to assault him.

Most witnesses weren't sure when the attacks occurred and gave varying accounts of how often.

When contacted by the St. Petersburg Times, the majority of their parents refused to speak on the record. They are worried about their sons, who they say have been rattled by the allegations against their teammates and the media attention that followed.

"We're putting it all behind us," said Hermeana Clark, one of the few parents willing to be quoted.

That might not be so easy. Experts say bullying can have a wide-ranging impact. It's not surprising that students who are bullied may experience depression, low self-esteem, health problems, poor grades and suicidal thoughts.

But researchers have found that observing bullying takes a toll as well, said Marlene Snyder, an associate professor at the Institute on Family and Neighborhood Life at Clemson University. Witnesses can be left feeling scared, powerless and guilty for not taking a stand.

Speaking generally about bullying, she said observers want to be seen as strong. They often align with the bully who wields power in hopes they won't become victims themselves.

"They're fearful that they're going to be the next one," Snyder said.

Parents of some witnesses said their children didn't understand the extent of the alleged abuse. They might have heard yelling or seen the attackers wielding sticks, but they didn't realize the boy was getting hurt or rationalized that he would speak up if things were that bad.

The victim's parents have said previously that he didn't tell them about the attacks because he worried they would take him off the team.

Concerns about social repercussions might also have been at play, some parents suggested. Younger students weren't eager to challenge their older, taller and athletically talented teammates.

One younger player confided to a reporter that all he wanted to do was get away. Months later, he regrets his silence.

Four teens each face four adult charges of sexual battery for abuse that spanned two months. The victim said Diemante J. Roberts, 15, and Raymond A. Price-Murray, 14, used a broom handle and hockey stick to assault him while 14-year-olds Randall John Moye III and Lee Louis Myers held him down.

He told detectives that "basically the whole team" was in the locker room when he was assaulted.

The Walker Middle School flag football team had 31 members, detectives said. In addition to the nine students listed as witnesses, 17 other students said they never saw anything happen to the victim.

The more people around to watch an incident, the less likely anyone is to report it, Snyder said.

"We kind of have the sense that someone else is going to report, that it's not up to us," she said.

As the director of development for the Olweus Bullying Prevention Program, Snyder urges schools to combat bullying by creating a culture that shifts power away from the students who bully to the students who try to do something about it.

She sees signs that Hillsborough school officials are taking the right steps to keep similar abuse from happening again.

Last month, she served as a keynote speaker at the Florida Association of School Administrators' conference in Orlando. The topic was bullying prevention, and the Hillsborough district required every school to have a representative attend.

Times researcher Will Gorham contributed to this report. Colleen Jenkins can be reached at cjenkins@sptimes.com or (813) 226-3337.